Bacterial Chemosensing pp 347-352 | Cite as
Quantitative Modeling of Flagellar Motor-Mediated Adaptation
Abstract
The bacterial flagellar motor is capable of adapting to changes in the concentrations of extracellular chemical stimuli by changing the composition of the switch complex of the flagellar motor. Such remodeling-based adaptation complements the receptor-mediated adaptation in the chemotaxis network to help maintain high sensitivity in the response of the motor to phospho-CheY concentrations, despite cell-to-cell variability in the abundances of chemotaxis proteins. In this chapter, a modeling approach is described that explains the mechanisms of switch-remodeling and motor-mediated adaptation. The approach is based on observations of structural differences, associated with the direction of motor rotation, that modulate the strength of FliM/FliN binding within the switch. By modulating the number of CheY-P-binding sites within the motor, remodeling maximizes sensitivity over a range of signal levels.
Keywords
Bacterial motility Chemotaxis Flagellar motors Switch complex Motor remodeling Ultrasensitivity Stochastic simulationNotes
Acknowledgment
This work was supported by funds from Texas A&M Engineering Experiment Station. The PI acknowledges support from the National Institute Of General Medical Sciences of the National Institutes of Health under Award Number R01GM123085. The content is solely the responsibility of the author and does not necessarily represent the official views of the National Institutes of Health.
References
- 1.Berg HC, Brown DA (1972) Chemotaxis in Escherichia coli analyzed by 3-dimensional tracking. Nature 239:500–504CrossRefGoogle Scholar
- 2.Yuan J, Branch RW, Hosu BG, Berg HC (2012) Adaptation at the output of the chemotaxis signalling pathway. Nature 484:233–236CrossRefGoogle Scholar
- 3.Dufour YS, Fu X, Hernandez-Nunez L, Emonet T (2014) Limits of feedback control in bacterial chemotaxis. PLoS Comput Biol 10:e1003694CrossRefGoogle Scholar
- 4.Branch RW, Sayegh MN, Shen C, Nathan VS, Berg HC (2014) Adaptive remodelling by FliN in the bacterial rotary motor. J Mol Biol 426:3314–3324CrossRefGoogle Scholar
- 5.Delalez NJ, Berry RM, Armitage JP (2014) Stoichiometry and turnover of the bacterial flagellar switch protein FliN. mBio 5:e01216–14CrossRefGoogle Scholar
- 6.Lele PP, Branch RW, Nathan VS, Berg HC (2012) Mechanism for adaptive remodeling of the bacterial flagellar switch. Proc Natl Acad Sci U S A 109:20018–20022CrossRefGoogle Scholar
- 7.Lele PP, Shrivastava A, Roland T, Berg HC (2015) Response thresholds in bacterial chemotaxis. Sci Adv 1:e1500299CrossRefGoogle Scholar
- 8.Cai X (2007) Exact stochastic simulation of coupled chemical reactions with delays. J Chem Phys 126:124108CrossRefGoogle Scholar
- 9.Turner L, Samuel ADT, Stern AS, Berg HC (1999) Temperature dependence of switching of the bacterial flagellar motor by the protein CheY(13DK106YW). Biophys J 77:597–603CrossRefGoogle Scholar
- 10.Tu Y (2013) Quantitative modeling of bacterial chemotaxis: signal amplification and accurate adaptation. Annu Rev Biophys 42:337–359CrossRefGoogle Scholar
- 11.Delalez NJ, Wadhams GH, Rosser G, Xue Q, Brown MT et al (2010) Signal-dependent turnover of the bacterial flagellar switch protein FliM. Proc Natl Acad Sci U S A 107:11347–11351CrossRefGoogle Scholar
- 12.Fukuoka H, Inoue Y, Terasawa S, Takahashi H, Ishijima A (2010) Exchange of rotor components in functioning bacterial flagellar motor. Biochem Biophys Res Commun 394:130–135CrossRefGoogle Scholar
- 13.Duke TA, Le Novère N, Bray D (2001) Conformational spread in a ring of proteins: a stochastic approach to allostery. J Mol Biol 308:541–553CrossRefGoogle Scholar
- 14.Bai F, Branch RW, Nicolau DV Jr, Pilizota T, Steel BC et al (2010) Conformational spread as a mechanism for cooperativity in the bacterial flagellar switch. Science 327:685–689CrossRefGoogle Scholar
- 15.Yuan J, Berg HC (2013) Ultrasensitivity of an adaptive bacterial motor. J Mol Biol 425:1760–1764CrossRefGoogle Scholar